Impact load deflector sleeve and removable collar assembly for cable and post protection

ABSTRACT

A guard system for protecting cables and posts from damage by falling rocks and other dynamic forces is provided. The guard assembly comprises a first sleeve rotatably positioned about the cable or post and a second sleeve rotatably positioned about the cable or post. A removable collar assembly is positioned between the first sleeve and the second sleeve for maintaining the spacing between the first sleeve and the second sleeve.

The present application is a continuation-in-part of pending patent application Ser. No. 10/976,201, filed on Oct. 28, 2004, entitled “CNC Impact Load Deflector Sleeve and Removable Collar for Cable and Post Protection”.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to an apparatus for the protection of cables and posts (or columns) against for cables and posts (or columns) against the dynamic loads from rolling stones, vehicular impact, ice impact or other forms of transient loads and, more particularly, the invention relates to a CNC impact load deflector sleeve and removable collar installable on the cable holding the fence post, which, in turn, stretches rock fall drape net, which constitutes a rock fall mitigation fence system (RFMFS).

2. Description of the Prior Art

A rock fall mitigation fence (RFMF) is frequently used to protect the traveling vehicles against potential hazards of falling rocks. The fence system is composed of the fence cable, fence posts, and rock fall drape net resting on the cable, which, in turn, is stretched and supported on the fence posts and cable anchors. The fence posts are embedded in rock and the cable is connected to the ground anchor embedded in rock. The RFMFS functions as a flexible fence system for retaining falling rocks by dissipating their dynamic energy during the back and forth swing upon rock impact. The mass of falling rocks varies a great deal. It can range from a few hundred pounds to many tons.

When falling from the hill/mountain top or slope, a falling rock gains momentum as it rolls down the slope. When it comes in contact with a RFMFS, the rock rotates at an extremely high angular velocity, can sever fence-supporting cables, and knocks out or severely bends fence posts, cuts anything it touches. The failure of the RFMFS allows the falling rocks to land on the highway or, in some cases, on top of a moving vehicle, as demonstrated in the rock fall in Georgetown, Colo. on Apr. 8, 2004. To date the only mechanism for the failure prevention of the RFMFS is to use stronger nets, cables and posts. The literature search including the search on the US Patent and Trademark web site and the communication with fence installers did not reveal any other fence cable or post protection apparatuses as the CNC Impact Load Deflector Sleeve (CNC//ILDS) and Removable Collar (RC) submitted in this invention that deflect the moving rocks and impact force, and, thereby, reduce the chance of cable and post failures. Accordingly there exists a need for a mechanism for deflecting falling rocks and impact force, reducing the chance of fence failure and enhancing the safety of the traveling public.

SUMMARY

The present invention is a guard system for protecting cables and posts from damage by falling rocks and other dynamic forces. The guard assembly comprises a first sleeve rotatably positioned about the cable or post and a second sleeve rotatably positioned about the cable or post near where it is anchored to the rock on the slope, if necessary. A removable collar assembly is positioned between the first sleeve and the second sleeve for maintaining the spacing between the first sleeve and the second sleeve.

In addition, the present invention includes a method for protecting cables and posts from damage by falling rocks and other dynamic forces. The method comprises providing at least one first sleeve cut to a desired length, positioning the first sleeve over the cable, inserting a holding screw through an aperture on each small sleeve contacting the cable, providing a second sleeve, positioning the second sleeve over the cable and first sleeve, tensioning the cable, looping a portion of the cable back onto itself, securing the looped end of the cable, sliding the second sleeve over the looped end, positioning a removable collar assembly between the first sleeve and the second sleeve, and removing the holding screws from the second sleeve.

The present invention further includes a guard system for protecting cables from damage by falling rocks and other dynamic forces. The guard assembly comprises at least one first sleeve rotatably positioned about the cable and a second sleeve rotatably positioned about the cable. A first removable collar is positioned between one of the first sleeves and the second sleeve. A second removable collar is releasably secured to the first removable collar. A slot is formed in each removable collar with the slot adapted for receiving the cable. A first aperture and a second aperture are formed in each removable collar on opposite sides of the slot. Fastening means are inserted through the first and second apertures of the first and second removable collars for releasably securing the first removable collar to the second removable collar wherein the slot of the first removable collar is substantially opposite the slot of the second removable collar, the first aperture of the first removable collar is substantially aligned with the second slot of the second removable collar, and the second aperture of the first removable collar is substantially aligned with the first aperture of the second removable collar.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view illustrating an impact load deflector sleeve and removable collar assembly for cable and post protection, constructed in accordance with the present invention, prior to a large sleeve being positioned over the looped cable;

FIG. 2 is a sectional view illustrating an impact load deflector sleeve and removable collar assembly for cable and post protection, constructed in accordance with the present invention, subsequent to the large sleeve being positioned over the looped cable;

FIG. 3 is a sectional view illustrating a pair of constructed removable collars of the impact load deflector sleeve and removable collar assembly for cable and post protection, constructed in accordance with the present invention, with the removable collars bolted together between a small sleeve and the large sleeve;

FIG. 4 is a side view illustrating the pair of constructed removable collars of the impact load deflector sleeve and removable collar assembly for cable and post protection, constructed in accordance with the present invention;

FIG. 5 is a top view illustrating a single removable collar of the impact load deflector sleeve and removable collar assembly for cable and post protection, constructed in accordance with the present invention; and

FIG. 6 is a top view illustrating the pair of constructed removable collars of the impact load deflector sleeve and removable collar assembly for cable and post protection, constructed in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As illustrated in FIGS. 1 and 2, the present invention is an impact load deflector sleeve and removable collar assembly, indicated generally at 10, for cable 12 and post protection. The impact load deflector assembly 10 of the present invention includes a plurality of small sleeves 14, a large sleeve 16, a plurality of washers 18 between each adjacent small sleeve 14, and a removable collar assembly 20 positioned between one of the small sleeves 14 and the large sleeve 16. The impact load deflector assembly 10 of the present invention allows the small sleeves 14 and the large sleeve 16 to deflect a rolling rock or other dynamic force upon contact and, thereby, reduces the failure potential of the fence cable 12.

The small sleeves 14 and the large sleeve 16 are preferably a cylindrical tube of any appropriate material made to loosely embrace a cable or a post to allow its near frictionless rotation about the cable or post. The length of the small sleeves 14 and the large sleeve 16 are determined by the field conditions present at the cable installation site and the desires of the construction team.

FIGS. 3-6 illustrate the removable collar assembly 20 of the impact load deflector assembly 10 of the present invention. The removable collar assembly 20 can be easily installed and removed from the cable 12 for easy construction and repair. The removable collar assembly 20 s are positioned between two different-size sleeves to prevent the smaller sleeve 14 from sliding or slipping into the large sleeve 16.

The removable collar assembly preferably includes a first removable collar 22 and a second removable collar 24. Each removable collar 22, 24 has a substantially circular cross-sectional configuration with a slot 26 formed therein extending from a perimeter of the removable collar 22, 24 to a point past a center point. In addition, each removable collar 22, 24 has a first aperture 28 and a second aperture 30 for receiving a bolt 32 or other releasable fastening mechanism.

To assemble or construct the removable collar assembly 20 for use with the impact load deflector assembly 10 of the present invention, first, the cable 12 or post is inserted into the slot 26 on the first removable collar 22. As illustrated in FIG. 6, the second removable collar 24 is positioned about the cable 12 or post such that the slots 26 of each removable collar 22, 24 are opposite each other. A first bolt 32 is inserted into the first aperture 28 of the first removable collar 22 and the second aperture 30 of the second removable collar 24 and a second bolt 32 is inserted into the second aperture 30 of the first removable collar 22 and the first aperture 28 of the second removable collar 24. A nut 34 or other tightening mechanism is releasably secured to each of the bolts 32 to maintain the first removable collar 22 to the second removable collar 24. Further construction of the impact load deflector assembly 10 will be discussed below.

The load impact deflector assembly 10 of the present invention reduces the impact load effect on both cables 12 and fence posts by deflecting the falling rocks upon contact. FIGS. 1 and 2 illustrate the load impact deflector assembly 10 installed about the cable 12. The small sleeves 14 and large sleeve 16 are preferably cylindrical and constructed from an appropriate material (e.g., steel) and have an appropriate diameter, length, and thickness for embracing a cable 12 or post with a clearance for near frictionless rotation. The thickness and material type of the sleeves 14, 16 are preferably selected to provide sufficient strength to prevent the puncture by the rolling rocks. The washers 18 can be positioned between adjacent small sleeves 14 to maintain the spacing of the small sleeves 14 and inhibit contact between adjacent small sleeves 14.

Upon contacting any high-speed rolling rock, the load impact deflector assembly 10 rotates nearly frictionless about the cable 12 and, thereby, avoids cable cut. It should be noted that the sleeves 14, 16 and removable collars 22, 24 can be constructed from any material deemed corrosion resistant, and sufficiently strong against the destructive force of rolling stones, wind, vehicular impact, or any other forms of impact force.

To mitigate the failure potential of a rock fall mitigation fence system, the sleeves 14, 16 of the load impact deflector assembly 10 can be installed along the entire length of the cable 12 and/or the post. The functionality of the load impact deflector assembly 10 is explained as follows:

The load impact deflector assembly 10 rotates nearly freely around the cable 12 and post that they are protecting.

Upon contacting a sleeve 14, 16, the impact force from a rolling rock or any other impact sources, causes the sleeves 14, 16 to rotate.

The action of sleeve rotation deflects the impact force and rock.

The deflection of the impact force reduces the damage potential of the cable 12 and post.

The removable collar assembly 20 is preferably installed between a small sleeve 14 at the lowest point of the cable 12 and a large sleeve 16 for protecting the connection just above the ground anchor and the small sleeve 12 for protecting the cable 12 right above the cable connection.

The construction of the load impact deflector assembly 10 of the present invention will now be discussed. As understood by those persons skilled in the art, the following description is just one manner of constructing the load impact deflector assembly 10.

First, the small sleeves 14 cut to a desired length according to field conditions are positioned over the cable 12 or post with a washer 18 between each adjacent small sleeve 14. The number of small sleeves 14 and washers 18 are dependent on the length of the cable 18 or post. A holding screw 36 is inserted through an aperture 38 on each small sleeve 14 and contacts the cable 12 or post to temporarily maintain the position of the small sleeve 14 on the cable 12 or post.

Second, as the end of the cable 12 or post is approached, the large sleeve 16 is positioned over the cable 12 and the small sleeves 14 (FIG. 1). In the case of a cable 12, the cable 12 is tensioned to the proper tension as specified by manufacturer recommendations and looped back onto itself. U-bolts 40 or other securement mechanism secures the looped end of the cable 12 and maintains the desired tension.

Third, the large sleeve 16 is moved over the U-bolts 40 (FIG. 2). Finally, the removable collar assembly 20 is constructed as described above between the large sleeve 16 and the adjacent small sleeve 14 and the holding screws 36 are removed from the small sleeves 14.

The removable collar assembly 20 of the impact load deflector assembly 10 inhibits the small sleeve 14 from slipping into the large sleeve 16. The fence system has to be structurally designed. Many instances of fence failures showed that the falling rocks severed the cables 12, and uprooted or severely bent the fence post. The failure of a rock fall mitigation fence system imposes a safety risk of traveling motorists from falling rocks as demonstrated in the recent rock fall event along Interstate Highway 170 near Georgetown, Colo. on Apr. 8, 2004. To reduce the risk of failure of a rock fall mitigation fence system, the fence cable needs to be protected from the cut by the large falling rock and the sleeve in the present invention provides such protection. In an event of need for sleeve replacement, the removable collar assembly 20 enhances the constructability because it can be easily opened and removed, the large sleeve 16 slips over the small sleeve 14 and cable 12 unbolted to allow sleeve 14, 16 removal and repair.

Besides, the impact force from falling rocks, the sleeves 14, 16 and removable collar assembly 20 of the impact load deflector assembly 10 of the present invention also provide a means of deflecting impact (or dynamic) forces, like those from vehicular impact, and ice impact, etc.

In sum, the sleeves 14, 16 and removable collar assembly 20 of the impact load deflector assembly 10 of the present invention are designed to provide a means of protecting fence cables 12 and posts. Without such protection, a conventional rock fall protection fence frequently fails upon impact from large falling rocks spinning at a high angular velocity and with an immense momentum, as demonstrated in many rock fall-induced fence failures. The sleeves 14, 16 embrace a cable 12 or post to deflect falling rocks spinning at a high angular velocity and associated impact forces and, thereby, protect them by avoiding detrimental blows from the falling rocks. The removable collar assembly 20 is used when two different-size sleeves are used avoiding a smaller sleeve 14 from slipping into a larger sleeve 16 and to assure the protection the sleeves 14, 16 are designed. Additionally, the removable collar assembly 20 enhances the constructability and eases the maintenance of a rock fall mitigation fence system. The sleeves 14, 16 together with the removable collar assembly 20 embraces the fence cable and post, provides a means of their protection, and enhances the safety of traveling motorists.

The foregoing exemplary descriptions and the illustrative preferred embodiments of the present invention have been explained in the drawings and described in detail, with varying modifications and alternative embodiments being taught. While the invention has been so shown, described and illustrated, it should be understood by those skilled in the art that equivalent changes in form and detail may be made therein without departing from the true spirit and scope of the invention, and that the scope of the present invention is to be limited only to the claims except as precluded by the prior art. Moreover, the invention as disclosed herein, may be suitably practiced in the absence of the specific elements which are disclosed herein. 

1. A guard system for protecting cables and posts from damage by falling rocks and other dynamic forces, the guard assembly comprising: a first sleeve rotatably positioned about the cable or post; a second sleeve rotatably positioned about the cable or post; and a removable collar assembly positioned between the first sleeve and the second sleeve for maintaining the spacing between the first sleeve and the second sleeve.
 2. The guard system of claim 1 wherein the diameter of the first sleeve is less than the diameter of the second sleeve.
 3. The guard system of claim 1 and further comprising: a plurality of first sleeves.
 4. The guard system of claim 4 and further comprising: at least one washer between each adjacent first sleeve.
 5. The guard system of claim 1 wherein the removable collar assembly includes a first removable collar and a second removable collar releasably secured to the first removable collar.
 6. The guard system of claim 5 wherein each removable collar has a slot for receiving the cable or post.
 7. The guard system of claim 6 wherein each the removable collar has a first aperture and a second aperture.
 8. The guard system of claim 7 wherein the guard assembly further comprises: the first removable collar positioned against the second removable collar such that the slot of the first removable collar is substantially opposite the slot of the second removable collar, the first aperture of the first removable collar is substantially aligned with the second slot of the second removable collar, and the second aperture of the first removable collar is substantially aligned with the first aperture of the second removable collar.
 9. The guard system of claim 8 and further comprising: fastening means inserted through the first and second apertures of the first and second removable collars for releasably securing the first removable collar to the second removable collar.
 10. The guard system of claim 1 wherein each sleeve is substantially tubular having a diameter greater than the diameter of the cable or post.
 11. A method for protecting cables and posts from damage by falling rocks and other dynamic forces, the guard assembly comprising: providing at least one first sleeve cut to a desired length; positioning the first sleeve over the cable; inserting a holding screw through an aperture on each small sleeve contacting the cable; providing a second sleeve; positioning the second sleeve over the cable and first sleeve; tensioning the cable; looping a portion of the cable back onto itself; securing the looped end of the cable; sliding the second sleeve over the looped end; positioning a removable collar assembly between the first sleeve and the second sleeve; and removing the holding screws from the second sleeve.
 12. The method of claim 11 and further comprising: providing a plurality of first sleeves; and positioning a washer between each adjacent first sleeve.
 13. The method of claim 11 wherein the first sleeve and the second sleeve are rotatable about the cable or post.
 14. The method of claim 11 wherein the removable collar assembly includes a first removable collar and a second removable collar releasably secured to the first removable collar.
 15. The method of claim 14 and further comprising: forming a slot in each removable collar for receiving the cable or post.
 16. The method of claim 15 and further comprising: forming a first aperture and a second aperture in each removable collar.
 17. The method of claim 16 and further comprising: positioning the first removable collar against the second removable collar such that the slot of the first removable collar is substantially opposite the slot of the second removable collar, the first aperture of the first removable collar is substantially aligned with the second slot of the second removable collar, and the second aperture of the first removable collar is substantially aligned with the first aperture of the second removable collar.
 18. The method of claim 17 and further comprising: inserting fastening means through the first and second apertures of the first and second removable collars for releasably securing the first removable collar to the second removable collar.
 19. A guard system for protecting cables from damage by falling rocks and other dynamic forces, the guard assembly comprising: at least one first sleeve rotatably positioned about the cable; a second sleeve rotatably positioned about the cable; a first removable collar positioned about the cable between one of the first sleeves and the second sleeve; a second removable collar releasably secured to the first removable collar; a slot formed in each removable collar, the slot adapted for receiving the cable; a first aperture and a second aperture formed in each removable collar on opposite sides of the slot; fastening means inserted through the first and second apertures of the first and second removable collars for releasably securing the first removable collar to the second removable collar; wherein the slot of the first removable collar is substantially opposite the slot of the second removable collar, the first aperture of the first removable collar is substantially aligned with the second slot of the second removable collar, and the second aperture of the first removable collar is substantially aligned with the first aperture of the second removable collar.
 20. The guard system of claim 1 wherein the diameter of the first sleeve is less than the diameter of the second sleeve. 